A communications network is a geographically distributed collection of interconnected communication links used to transport data between nodes, such as routers, switches, computer systems and so on. Many types of communications networks exist, with types ranging from local area networks (LANs) to wide-area networks (WANs). The nodes typically communicate by exchanging discrete messages of data (e.g., data packets) according to pre-defined protocols.
Many users gain access to a communications network, such as the Internet, through a Service Provider (SP). Here, a user may enter into a subscription to subscribe to the SP's services. The services may include provisions for allowing subscribers to gain access the network using end nodes (e.g., a computer systems operated by the subscribers). After gaining access to the network, a subscriber may exchange information, such as electronic mail (e-mail), text, graphics, images, web pages, files and so on, with other subscribers that also have access to the network.